Objective: To detect the cell-surface-expressed nucleolin and investigate its tumor suppressing effect on the growth of hepatocellular carcinoma cells.
Methods: To detect cell-surface-expressed nucleolin in the hepatocellular carcinoma cells by immunofluorescence and flow cytometry. To down-regulate the nucleolin expression level in hepatocellular carcinoma cells by RNA interference. The tumor-suppressing effect of cell-surface nucleolin on hepatocellular carcinoma cells was assessed by MTT and transwell chamber assays.
Results: Nucleolin was expressed in the nuclei, cytoplasm and on the cell surface of hepatocellular carcinoma cells. ShRNA markedly decreased the nucleolin expression level in the cytoplasm and on the cell surface (P < 0.01), but the nuclear nucleolin remained unchanged. After downregulation of cell-surface nucleolin, MTT assays showed that the cell growth rate of hepatocellular carcinoma cells in the shRNA interference group was significantly inhibited as compared with that in the control group (P < 0.01). The transwell chamber assay showed that the mean transmembrane cell number in the shRNA interference group was significantly lower than that in the control group.
Conclusion: The results of this study show that downregulation of cell-surface nucleolin expression inhibits the growth of hepatocellular carcinoma cells in vitro.